Abstract
Perceptual learning can occur in either the visual or auditory modality when a subject is trained to discriminate similar stimuli. The present study addressed the possibility of simultaneous perceptual learning in both the auditory and visual domains. Additionally, the effects of a comprehensive pretest prior to training in either modality were examined. We have called this comprehensive pretest a “perceptual syllabus” as it is meant to organize the learning much as a course syllabus does. The visual task involved line orientation discriminations. The auditory task consisted of discriminating the pitch of tones. The subjects' task in both modalities was to say whether two very similar stimuli were “same” or “different.” 24 subjects were trained on both tasks over seven experimental sessions. Subjects were divided into three groups: Auditory Syllabus, Visual Syllabus, and No Syllabus (control). On the first day, the subjects in the Visual Syllabus group were given a pretest including discriminations of four orientation and retinal location combinations. The Auditory Syllabus group received a pretest with four pitch sets. For the next five sessions, all participants were trained on one visual (i.e. one orientation set at one retinal location) and one auditory condition. All participants were then given a comprehensive posttest on all four conditions for both modalities. Results indicate that compared to previous studies training on either visual or auditory domains, simultaneous modality training produced smaller increases in performance for all groups. Additionally, subjects given a syllabus in one task (visual or auditory) showed a trend toward better performance during training on the task not given a syllabus. We propose that this may result from a recruitment of neighboring cells to improve performance when a task is specific, but a resistance to doing so when a perceptual syllabus has suggested that a broader sensitivity may remain important.
NSERC to KMO and the Rotman Research Institute